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101.
SRIVASTAVA Z. I.; MATHUR N.; RASTOGI S. K.; GUPTA B. N. 《Occupational medicine (Oxford, England)》1988,38(4):134-136
Eighty-nine cases of chronic bronchitis were matched against167 asymptomatic controls from the glass bangle industry ofFirozabad. Factors of age, social status, smoking habit andduration of exposure were studied. Duration of exposure wasfound to be a factor contributing significantly to the causationof disease.
Requests for reprints should be addressed to: Dr B. N. Gupta, Division of Epidemilogy, Industrial Toxicology Research Centre, Mahatma Gandhi Marg, Lucknow P.O. Box 80, 226001, India 相似文献
102.
103.
I K Shkhvatsabaia A N Kravchenko P V Avdonin M Iu Men'shikov A A Nekrasova 《Kardiologiia》1988,28(5):72-77
Platelet activation factor (PAF)-, ADP and vasopressin-induced increments of platelet Ca2+ concentration were measured by quin-2 in 64 patients with essential hypertension and 16 normal donors. Basal concentration of free Ca2+ was 87 +/- 4 nM in donors, 106 +/- 5 nM in patients with labile hypertension (LH) and 122 +/- 6 nM in those with stable hypertension (SH) (p less than 0.01). PAF, ADP and vasopressin, added to platelets, increased [Ca]in by 448 +/- 58, 397 +/- 66, and 277 +/- 50 nM, respectively, in the donors, by 473 +/- 57, 479 +/- 54 and 195 +/- 32 nM, in LH patients, and by 607 +/- 85, 584 +/- 73 and 245 +/- 41 nM in SH patients. There were no significant variations between the three samples, using the ANOVA test. In 20 patients, whose both parents had essential hypertension, [Ca]in increment was 738 +/- 8 nM for PAF, 682 +/- 90 nM for ADP, and 320 +/- 61 nM for vasopressin. In 19 patients, who admitted to no essential hypertension in the family, these parameters were significantly lower: 310 +/- 40 nM for PAF, 389 +/- 61 nM for ADP, and 147 +/- 26 nM for vasopressin. The demonstrated changes may be making an important contribution to the maintenance of elevated vascular tone and provide an evidence in favor of a genetically-predetermined EH variety. 相似文献
104.
This study investigates the contribution of body fat stores on the age-associated increase in serum cholesterol and triglyceride levels. Percentage of body fat was measured by hydrostatic weighing, and serum cholesterol, triglyceride, low-density lipoprotein cholesterol, and high-density lipoprotein cholesterol levels were determined in a sample of 472 healthy men and women ages 18-50 years. In both sexes, body fat mass was significantly correlated with serum cholesterol (r = 0.21 in men and r = 0.24 in women, P less than 0.01) and triglyceride (r = 0.33 in men and r = 0.24 in women, P less than 0.01) levels. After adjustment for the association between age and serum cholesterol, no correlation was observed between body fat mass and serum cholesterol (r = 0.01 in men and r = 0.09 in women). After correction for age, serum triglyceride levels remained significantly correlated with body fat mass (r = 0.26 and r = 0.17 in men and women, respectively, P less than 0.05). As body fat also increases with age, the possibility that a partial correlation coefficient procedure eliminated a portion of the age effect mediated by an age-related increase in fat, was addressed by performing further analyses. Within each sex subsample two sets of analyses were performed on (a) three groups of subjects individually paired for age but with different levels of body fat stores, and (b) three groups of subjects paired for the amount of body fat but differing in age.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
105.
R. P. Heaney T. M. Zizic I. Fogelman W. P. Olszynski P. Geusens C. Kasibhatla N. Alsayed G. Isaia M. W. Davie C. H. Chesnut III 《Osteoporosis international》2002,13(6):501-505
Risedronate treatment reduces the risk of vertebral fracture in women with existing vertebral fractures, but its efficacy
in prevention of the first vertebral fracture in women with osteoporosis but without vertebral fractures has not been determined.
We examined the risk of first vertebral fracture in postmenopausal women who were enrolled in four placebo-controlled clinical
trials of risedronate and who had low lumbar spine bone mineral density (BMD) (mean T-score =–3.3) and no vertebral fractures at baseline. Subjects received risedronate 5 mg (n= 328) or placebo (n= 312) daily for up to 3 years; all subjects were given calcium (1000 mg daily), as well as vitamin D supplementation (up
to 500 IU daily) if baseline serum 25-hydroxyvitamin D levels were low. The incidence of first vertebral fracture was 9.4%
in the women treated with placebo and 2.6% in those treated with risedronate 5 mg (risk reduction of 75%, 95% confidence interval
37% to 90%; P= 0.002). The number of patients who would need to be treated to prevent one new vertebral fracture is 15. When subjects were
stratified by age, similar significant reductions were observed in patients with a mean age of 64 years (risk reduction of
70%, 95% CI 8% to 90%; P= 0.030) and in those with a mean age of 76 years (risk reduction of 80%, 95% CI 7% to 96%; P= 0.024). Risedronate treatment therefore significantly reduces the risk of first vertebral fracture in postmenopausal women
with osteoporosis, with a similar magnitude of effect early and late after the menopause.
Received: 12 September 2001 / Accepted: 11 December 2001 相似文献
106.
Oral allergy syndrome induced by spinach 总被引:1,自引:1,他引:0
I. Sanchez F. Rodriguez J. L. Garcia-Abujeta L. Fernandez D. Quiñones D. Martin-Gil 《Allergy》1997,52(12):1245-1246
107.
M. A. García-Pérez C. Climent P. Briones M. A. Vilaseca M. Rodés V. Rubio 《Journal of inherited metabolic disease》1997,20(6):769-777
Mutations P225L and P225R were identified in codon 225 of the gene for ornithine transcarbamylase (OTC) in two patients with the neonatal form of OTC deficiency. The mutations occur at a CpG dinucleotide and eliminate a unique MspI restriction site in exon 7 of the OTC gene. They do not alter existing splice sites or create new sites, as judged from the nucleotide sequence. Both mutations are associated with undetectable levels of OTC antigen in liver homogenates, and with either complete lack of OTC activity (P225R mutation) or very small residual activity (0.15% of normal in the P225L mutation). The residual activity observed with P225L exhibits normal pH dependence, little or no increases in the Km values for ornithine and carbamoyl phosphate and normal stability at either 37°C or, in the presence of 0.66 mol/L urea, at 0°C. The latter conditions were used to examine whether the P225L mutation favours dissociation of the active OTC trimer. Given the normal stability and lack of tendency to dissociation of the mutant enzyme, it appears likely that the dramatic reduction in the level of OTC protein is due to inefficient conversion of the mutant OTC precursor polypeptide (pOTC) into the correctly localized, appropriately folded, mature enzyme trimer, suggesting degradation of pOTC in transit to the mitochondria. 相似文献
108.
Congenital intermaxillary fusion is a rare anomaly. Combination of the anomaly with any type of facial cleft is extremely rare. Death in a majority of these patients as a result of feeding and aspiration problems in early life may have caused the reports to be limited. In this article a 5-year-old patient, probably the first in the literature having Tessier type VI-VII facial cleft combination associated with bimaxillary fusion and anophthalmia on the right side, is presented. The patient has survived on fluid meal through a very small opening for 5 years. The features of the case are presented, and the time and method of the management of such a rare anomaly are discussed with a review of the literature. 相似文献
109.
M. NEUBRAND I. GREINWALD H. LOBENTANZER G. PAUMGARTNER H. HERMEKING T. SAUERBRUCH 《European journal of clinical investigation》1997,27(3):234-241
Efficient fragmentation is the most important prerequisite for successful treatment of gallstones by extracorporeally induced shock waves. No data are available on the amount of energy necessary for stone disintegration and on the threshold energy below which no further fragmentation occurs. We therefore performed an in vitro investigation on human cholesterol gallstones to elucidate physical laws governing shock-wave lithotripsy. First, the focal pressure of the lithotripter was measured to calculate the energy traversing a stone. Second, 96 gallstones from 16 gall bladders were analysed with respect to physicochemical composition, radiological features and ultrasound before fragmentation was performed. Energy for stone disintegration was constant within each stone family but varied between 4.6 J mL?1 and 36.8 J mL?1 in different families. This energy correlated linearly with stone volume. None of the radiological and physicochemical factors revealed a clear-cut correlation of the different energies necessary for similar stone disintegration. The threshold energy differed between 0.26 mJ and 1.04 mJ per pulse. In conclusion, stone volume was the best parameter predicting stone fragmentation. However, in cholesterol stones with a similar composition the required energy per volume varies considerably together with the threshold energy. Radiological and ultrasound parameters appear to be of minor importance in explaining these differences. 相似文献
110.